How does Michael Ondaatje use imagery in To a Sad Daughter?

The third stanza gives us a look at the father's main concerns involving his daughter's future. Some parents may find his advice unthinkable and even dangerous, but Ondaatje delivers such a compelling rationale that we cannot help but understand he has the girl's best interest in mind. In the first five lines, the poet uses striking mythological imagery to make his "cautionary" point, although we may see it as "reverse" caution, since he urges her to do exactly the opposite of what many fathers would advise. In mythological tales, sirens were sea nymphs whose sweet singing lured unsuspecting sailors to their island. The catch was that the island was surrounded by craggy rocks, and the mariners met their fate when their ships were destroyed by the hidden danger. Eventually, some sailors learned to cover their ears and pass the seductive singing without falling victim to it, but many failed. In this poem, the father tells his daughter, "One day I'll come swimming/beside your ship or someone will / and if you hear the siren / listen to it." This may sound like astonishing advice, as the father tells his daughter to follow a path to sure destruction, but he offers his reasons in the next lines: "For if you close your ears / only nothing happens. You will never change." Here, the poet indicates that "change" is vital to growth and to living a fulfilling life. He would rather his daughter take risks and discover what the world has to offer than to hide away in a protective shell where "nothing happens" but the same experiences, the same thoughts, the same beliefs.